Turner Reich 300mm triple convertible question
I have a Turner Reich 300mm triple convertible II lens. The lens has markings for many different combinations of 14", 18" 24" and 28" lenses, but no markings for using them seperately. I have the 18'' and 28" and I was wondering what the f stops are when I use them by them selves.
The max opening used combined are f6.8.
The two lenses together with the front element in front is 14". The 18 and 28 elements used alone in the rear of the shutter are the focal length indicated on them.
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Well I wasn't asking for focal length, but the maximum aperture opening when the lenses are used alone. Anyway on my lens the 28"/18" combination is indicated as being 11 1/2".
What's the difference in using them alone in the front or in the rear. Used in the front the 18" seems to be at it's right focal length, and I cannot focus the 28" since I only have 520mm of bellows draw at present.
Anyway, thanks for the answer.
i am sort of confused by your question ..
if the lens is a triple convertible, there should
be 3 different markings with fstop markings
right on the lens. if it isn't marked, you could divide
the max fstop opening into the focal length and that will give you
the fstops you are wondering about ...
i hope i got that right
So you have a triple convertible in an unoriginal shutter?
The combined lens is a bit less than half the focal length of the 28" element, so using that alone would give a bit less than two stops darker than the whole lens - f:8 on the scale would be f:18 or so (well within the tolerance of the shutter speeds).
The 18" is about 1 2/3 stop slower than the whole thing, so if I were you I would simply measure the opening of the aperture and use that to make a new table - thirds are too difficult to remember in the field.
Placing the single cell behind the shutter gives better correction fo rdistortion and some other aberrations. If you want soft, use it in front.
-- Ole Tjugen, Luddite Elitist
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Mads, I don't know if this will answer your question but here goes! I have a TRT 12", 21" 28" and the max f- stops are 6.8, 12.5, 16. I hope this is the info you need. Mine is in a Betax #4.
Originally Posted by loman
If it helps, I have 2 TRT lens, both are 12", 19.7" & 25"; the maximum f-stops are f7, f12.5, and f16. One of the lens is in an Ilex No. 4 Acme and the other in a Betax #4.
I found my old Gundlach Catalog and it states that your lens is a double anastigmat. The 18" and 28" which combine to make an 11 1/2" had a maximum aperture of f7.5. It came in a No. 4 Betax, #4 Optimo, #4 Ilex Universal, #4 Ilex Acme, and a #5 Compound shutter.
Hope this helps. Jon
Everyone has a constitutional right to be an idiot; that does not mean you should exercise your right!
Jim, that is the same as my 12"-21"-28". (Series II, No.5)
It is interesting the variety of TRs Triples there are. I have never heard of one which was marked in four focal lengths, though, such as Mads mentioned.
Vaughn, I got one of the good ones I think. Very little edge separation and the shutter is spot on. Seems to give me nice contrast and a good look even with a filter on when I use it at 21". It is a little heavy but it is great to have these lengths for the 8x10. Unfortunately I only have about 25" extension on the Seneca. I may use the 28" component on the 8x20. The longest lens I have for the 8x20 is a Kodak 21 1/4" lens.
Originally Posted by Vaughn
Thanks Everybody for your answers
Mine is in an Ilex universal shutter, and I think the fstop scale has been replaced at some point. It's quite impressive, there are f stops engraved for six different combinations of lenses, but for none of them used seperately.
And there is no more room on the shutter to engrave anything.
I think I have the information I need now, and I'll just have to write it down on a piece of paper and refer to that when I'm "out in field".
By the way Ole thanks for the info on the differences of mounting the cells in front or behind the shutter.
That brings me to another question:
I have a 300mm symmar linhof selected lens, in a compound 4 shutter. When I use the rear 500mm cell by it self I cannot focus it at all even with max bellows draw, but if I mount it in front of the shutter I can! Can somebody explain this to me?